https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93754
Bug ID: 93754 Summary: [GCOV] incorrect coverage for user-defined "free" function Product: gcc Version: 9.2.0 Status: UNCONFIRMED Severity: normal Priority: P3 Component: gcov-profile Assignee: unassigned at gcc dot gnu.org Reporter: yangyibiao at hust dot edu.cn CC: marxin at gcc dot gnu.org Target Milestone: --- $ gcov -v gcov (GCC) 9.2.0 Copyright (C) 2019 Free Software Foundation, Inc. This is free software; see the source for copying conditions. There is NO warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. $ gcc -v Using built-in specs. COLLECT_GCC=gcc COLLECT_LTO_WRAPPER=/usr/lib/gcc/x86_64-pc-linux-gnu/9.2.0/lto-wrapper Target: x86_64-pc-linux-gnu Configured with: /build/gcc/src/gcc/configure --prefix=/usr --libdir=/usr/lib --libexecdir=/usr/lib --mandir=/usr/share/man --infodir=/usr/share/info --with-bugurl=https://bugs.archlinux.org/ --enable-languages=c,c++,ada,fortran,go,lto,objc,obj-c++,d --enable-shared --enable-threads=posix --with-system-zlib --with-isl --enable-__cxa_atexit --disable-libunwind-exceptions --enable-clocale=gnu --disable-libstdcxx-pch --disable-libssp --enable-gnu-unique-object --enable-linker-build-id --enable-lto --enable-plugin --enable-install-libiberty --with-linker-hash-style=gnu --enable-gnu-indirect-function --enable-multilib --disable-werror --enable-checking=release --enable-default-pie --enable-default-ssp --enable-cet=auto gdc_include_dir=/usr/include/dlang/gdc Thread model: posix gcc version 9.2.0 (GCC) #### code for small.c #### $ cat small.c void free(void *ptr) { return; } void *foo() { return 0; } void main() { void *p = foo(); free(p); } #### coverage generated by gcov #### $ gcc -O0 --coverage small.c; ./a.out; gcov small.c; cat small.c.gcov File 'small.c' Lines executed:100.00% of 8 Creating 'small.c.gcov' -: 0:Source:small.c -: 0:Graph:small.gcno -: 0:Data:small.gcda -: 0:Runs:1 2: 1:void free(void *ptr) -: 2:{ 2: 3: return; -: 4:} -: 5: 1: 6:void *foo() -: 7:{ 1: 8: return 0; -: 9:} -: 10: 1: 11:void main() -: 12:{ 1: 13: void *p = foo(); 1: 14: free(p); 1: 15:} ##################### Function "free" is called only once in Line #14. However, we can find that Line #1 and #3 are wrongly marked as executed twice.